H-Transfer Mediated Self-Enhanced Interphase for High-Voltage Lithium-Ion Batteries
Shihao Duan, Shuo‐Qing Zhang, Yong Li, Rui Guo, Ling Lv, Ruhong Li, Zunchun Wu, Menglu Li, Shunrui Xiao, Lixin Chen, Yong Shi, Tao Deng, Xiulin Fan
Abstract
The dehydrogenation of solvents presents a significant challenge at the cathode–electrolyte interface (CEI) in high-voltage lithium-ion batteries (LIBs), resulting in the generation of corrosive HF and posing detrimental effects on the sustainability of LIBs. Herein, we propose an interfacial self-enhanced strategy mediated by H-transfer to mitigate solvent dehydrogenation at the CEI. As a proof of concept, trimethyl phosphate (TMP) was coupled with 1,1,2,2,3,3,4-heptafluorocyclopentane (HFCP) to prepare the high-voltage electrolyte, where TMP serves to capture H free radicals produced by the dehydrogenation of HFCP, while the dehydrogenated-HFCP radicals would in situ passivate the cathode/electrolyte interface. The TMP/HFCP electrolyte enables a 4.4 V graphite||LiNi 0.8 Co 0.1 Mn 0.1 O 2 LIB to achieve over 90% capacity retention after 1300 cycles at 0.5 C. Furthermore, the TMP/HFCP electrolyte exhibits favorable properties in terms of nonflammability and minimal gas production during electrochemical and thermal tests. This work presents a promising pathway for realizing high-voltage and high-safety LIBs.